He was Defence Secretary of India during the Indo-Pakistani war of 1971.
Ambassador Lall was also accredited to the Grand Duchy of Luxembourg.
In this capacity he inaugurated with the former Minister of Foreign Affairs of Luxembourg, Mr. Gaston Thorn, the bust of Mahatma Gandhi in the Municipal Park in Luxembourg-City on 21 June 1973.
The bronze bust sculpture by the famous modernist artist Amar Nath Sehgal (1922-2007) was a gift by the philanthropist Henry J. Leir.
Greatly respected by Defence minister Jagjivan Ram, Lall's stewardship of the Ministry of defence contributed materially to the smooth conduct of, and victory in the 1971 War.